80C186EC/80C188EC Microprocessor User's Manual

INSTRUCTION SET DESCRIPTIONS
Table C-3. Flag Bit Functions
Name
AF
CF
DF
IF
OF
PF
SF
TF
ZF
Function
Auxiliary Flag:
Set on carry from or borrow to the low order four bits of AL; cleared otherwise.
Carry Flag:
Set on high-order bit carry or borrow; cleared otherwise.
Direction Flag:
Causes string instructions to auto decrement the appropriate index register
when set. Clearing DF causes auto increment.
Interrupt-enable Flag:
When set, maskable interrupts will cause the CPU to transfer control to an
interrupt vector specified location.
Overflow Flag:
Set if the signed result cannot be expressed within the number of bits in the
destination operand; cleared otherwise.
Parity Flag:
Set if low-order 8 bits of result contain an even number of 1 bits; cleared
otherwise.
Sign Flag:
Set equal to high-order bit of result (0 if positive, 1 if negative).
Single Step Flag:
Once set, a single step interrupt occurs after the next instruction executes. TF
is cleared by the single step interrupt.
Zero Flag:
Set if result is zero; cleared otherwise.
C-3